As an admitted amateur rather than a pro, I use Model Master paints (made by Testors, the illegitimate descendants of the once mighty Polly-S). RAF Dark Earth, RAF Green, and the one known as Sky Type S (see Dom, I've learned some things from you about that shade! ). For North Africa it's Dark Earth, Azure Blue, and Middlestone, unfortunately Testors in their wisdom stopped producing Middlestone about a year ago (I've got 3 bottles of real Polly-S Middlestone squirreled away but you can't have them).

A buddy of mine uses Tamiya primarily and their colors look good too, so either brand should be o.k., though I don't know what names Tamiya uses for the appropriate colors.

Camo patterns were factory applied, either the A scheme or the B scheme. I'm pretty sure they can be found on the Wings Palette site:

Tamiya have recently issued paints for the late war RAF Day Fighter Scheme, so XF-81 RAF Dark Green takes care of the green part of the Temperate Land Scheme used in the Battle of Britain.

The Dark Earth used in both the Temperate Land Scheme and the Desert Scheme and the Middle Stone of the Desert Scheme both need to be mixed. On their instruction sheets, Tamiya recommend a mix of 1 part XF-52 Flat Earth to 1 part XF-64 Red Brown for Dark Earth, and 1 part XF-59 Desert Yellow to 1 part XF-60 Dark Yellow for Middle Stone.

For the undersurfaces, Battle of Britain types can be finished in Tamiya's XF-21 Sky, though it looks a bit too green to me, or in one of several shades of duck egg blue, duck egg green or eau-de-nil to taste, while the desert types would be in Azure Blue, mixed from 2 parts X-16 Purple, 10 parts XF-2 Flat White and 5 parts XF-18 Medium Blue.

The nice thing about the Tamiya paints is identical colors in bottles and spray cans. I generally spray the undersides of the planes first. When dry, flip the models and spray the lighter shade of the two color camo pattern on the top surfaces holding the spray can slightly higher than normal and as vertical as possible. Then brush paint the darker camo color on the upper surfaces. Thinner paint works better than thick for this step. This process has always worked well for me. Touch up is also easy as the brush paints match the spray paints.